Thinking about a Center Mount Fan Shroud.
I am reading conflicting information on how center mounts cool. Some say it is great. Other say it is the Worst.
I also read about DTM
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Thinking about a Center Mount Fan Shroud.
I am reading conflicting information on how center mounts cool. Some say it is great. Other say it is the Worst.
I also read about DTM
I am reading conflicting information on how center mounts cool. Some say it is great. Other say it is the Worst.
I also read about DTM
The fan on the back of the generator sucks, not blows. Putting an oil cooler anywhere near it will just help hot air to be drawn into the "cooling" shroud.
To save a lot of time and research for you, I'd recommend:
1. A full, standard VW doghouse shroud
2. A 36hp style doghouse shroud, which claims to have all internal ducting in place.
Anything else is not fit for the street.
The exception being Jake Raby's T1 DTM kit, which by all accounts performs really well, potentially at the expense of heat exchanger outlets and thermostat flaps to aid warm up (you'd normally lose the flaps with option 2 anyway)
External oil coolers are great, but don't cool the oil sufficiently when the vehicle is stationary. Something close to the original VW system is the best starting point. Oh. and don't mount the oil cooler behind the fan shroud. You'll just be heating the air which flows over the cylinders, not the best idea.
1. A full, standard VW doghouse shroud
2. A 36hp style doghouse shroud, which claims to have all internal ducting in place.
Anything else is not fit for the street.
The exception being Jake Raby's T1 DTM kit, which by all accounts performs really well, potentially at the expense of heat exchanger outlets and thermostat flaps to aid warm up (you'd normally lose the flaps with option 2 anyway)
External oil coolers are great, but don't cool the oil sufficiently when the vehicle is stationary. Something close to the original VW system is the best starting point. Oh. and don't mount the oil cooler behind the fan shroud. You'll just be heating the air which flows over the cylinders, not the best idea.
Agree with Jon; definitely stay away from the center mounts!! They'll cook your engine!
An external oil cooler with a thermostatically controlled electric fan is good investment if you are in hot climate (AZ/TX/FL/GA or sit in traffic a lot (CA, No VA!) If in a cold environment use a theromatic controlled valve to bypass the cooler when oil is cold. Can be mounted over the transaxel, in a wheel well (protect with screen from stones) or under the rear deck grill (although an electric fan won't fit there). I'd recommend stainless steel covered lines over rubber hose - and make sure they don't rub anything.
Todd, the underside of my decklid had to go for the DTM to fit.
If you've got a Type IV and you want to keep it cool, I'd really suggest it. Jake sends out a videotape with them -- I'll be happy to mail it to you.
I haven't got an engine compartment made yet, and my car's temperatures have been nowhere near the 'time to worry about the temps, dummy,' range. I don't think it's coincidental.
If you've got a Type IV and you want to keep it cool, I'd really suggest it. Jake sends out a videotape with them -- I'll be happy to mail it to you.
I haven't got an engine compartment made yet, and my car's temperatures have been nowhere near the 'time to worry about the temps, dummy,' range. I don't think it's coincidental.
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I read about everything I could with regard to the cooling shrouds and their shapes. I really wanted one that looked similar to either a 911 or better still, the Carrera 4 cam. I even bought one shroud off of the SAMBA which just plane didn't fit the VW 1776, but now looks great atop my mailbox.
For cooling information Jake has gone to great lengths and he believed in the DTM enough to revitalize its design. John at JPS has used a cute centered-looking unit on a lot of his builds and I haven't read where anyone bit the big one as a result.
For a 1776 a dog house is fine. It served a gazillion VWs before us! A DTM, in my opinion does work better than a dog house, but you only need so much cooling. There is merit to the cooling distribution with the DTM which is better than a dog house and better than the center-hump unit.
Yes, I have a DTM and yes it fits in my engine bay. The hose at the top gets crunched a little and that is an aesthetic thing, not a performance bug-a-boo. But then I have a little more cooling need and demand and I trusted the engine's builder with the list of required ancillary cooling things to keep my engine happy...
Placement of the oil cooler and I assume accompanying fan? I placed mine up behind the firewall in the space between the firewall and back of the backseat. It stays clean, can be accessed OK and doesn't create any lower point of conflicts with speedbumps, etc.
A neat look I am investigating for my next build is to have it upfront with lines running to the back of the car. My 930 had this and in pictures of 356 Carrera GTs and GSs, you'll see the two lines in the front right wheel well. Not an original idea, but one that seems to work when planned for in the initial stages of a build.
For cooling information Jake has gone to great lengths and he believed in the DTM enough to revitalize its design. John at JPS has used a cute centered-looking unit on a lot of his builds and I haven't read where anyone bit the big one as a result.
For a 1776 a dog house is fine. It served a gazillion VWs before us! A DTM, in my opinion does work better than a dog house, but you only need so much cooling. There is merit to the cooling distribution with the DTM which is better than a dog house and better than the center-hump unit.
Yes, I have a DTM and yes it fits in my engine bay. The hose at the top gets crunched a little and that is an aesthetic thing, not a performance bug-a-boo. But then I have a little more cooling need and demand and I trusted the engine's builder with the list of required ancillary cooling things to keep my engine happy...
Placement of the oil cooler and I assume accompanying fan? I placed mine up behind the firewall in the space between the firewall and back of the backseat. It stays clean, can be accessed OK and doesn't create any lower point of conflicts with speedbumps, etc.
A neat look I am investigating for my next build is to have it upfront with lines running to the back of the car. My 930 had this and in pictures of 356 Carrera GTs and GSs, you'll see the two lines in the front right wheel well. Not an original idea, but one that seems to work when planned for in the initial stages of a build.
On a related note; just want to show you some photos of a 11" by 2" scoop fabbed out of a piece of light gauge aluminum by a friend of mine. As per Gene Berg's recommendation this is a way to increase air flow into your engine compartment. The front engine tin has been punched to fit a 2" diameter fresh air hose which is hooked up to the scoop at the other end. The scoop will be mounted atop the right rear torsion bar area (which is a low pressure area). Now that my transaxle is back in the car (thanks Jjr!) and the engine hasn't gone back in it's a good time for retrofitting. Let's hope it works!
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I've read that the fan shroud flappers and thermostat on a type 1 fresh air fan shroud set-up help with cooling.
I don't have data to verify this, but I think they are worth leaving (or adding) to the type 1 fan shroud.
I left the flappers locked in an open position, on the 2074 Motor in my Speedster.
(This was just to be a test. I didn't want to hassle the thermostat and linkage.. so I just fixed flappers in full open position)
The firewall also has an opening to match the fan intake of the Motor. So far no overheat problems.
I'm thinking of closing the hole in the firewall for Winter driving as it takes Soooo long to warm up.
Summer driving with this set up hasn't seen oil temps of 210 degrees*, so far.
Greg
* The engine has the Dog house type fan shroud and oil cooler. The shroud is altered to accept the larger 914 oil cooler. Also included is a large external oil cooler (96 plate) under the transaxle and full flow oil filter set up.
Thanks for the input. Based on what I read, I decided to go with a standard shroud. I am having it powder-coated Guard Red as we speak.
Todd
Todd
Greg; don't close off the hole in the firewall; just hook up your thermo system and unlock the flaps so they work like they're supposed to and it'll warm up a lot quicker in the winter yet give you the flexibility to be able to use it in the summer as well without moving a finger.
Todd; I commend you on your wise decision; you won't regret it.
Todd; I commend you on your wise decision; you won't regret it.
Your paint selection (color and application) sound great! The only thing I don't like about my set up is how it looks. Oh well, its merits I guess were suppose to be the beauty. Still, it makes my engine look sort of new, rather than old-school P-car.
Just thought I'd chime in here, albeit very late. This is the set-up that I'm going to be using on my 2.0 type 4 built by a local South African. Very close to a stock beetle set-up.
http://img361.imageshack.us/img361/395/myimpiengine23os.jpg
http://img361.imageshack.us/img361/395/myimpiengine23os.jpg
Excellent decision, Todd.